A bicycle can get a rider places quickly without gobbling fossil fuels like gasoline, diesel, and coal or creating pollution. Bicycles can do so by efficiently converting the power a rider produces into kinetic energy (energy of movement). Normally, bicycles include a drive chain system wherein the rider can rotate a crankshaft by applying force against a pair of pedals connected to crank arms with the rider's feet. The drive chain system of a bicycle typically includes a forward sprocket, or chainring, attached to the crankshaft, and a rear sprocket, or cog, linked to the forward sprocket by a tension chain. Opposing crank arms perpendicularly attach to and extend from opposite sides of the forward sprocket, and pedals are pivotally attached to each crank arm end. When the rider pedals, the forward sprocket rotates in a unidirectional angular direction. As the forward sprocket rotates, the tension chain causes the rear sprocket to turn, which is connected to the rear wheel and thus drives the bicycle to move forward.
The bicycle is a tremendously efficient means of transportation. In fact, cycling is more efficient than any other method of travel—including walking. The development of drive chain system helped make the modern-day bicycle possible. With the advent of gears, the rider can pedal efficiently, enjoying increased speed and easy riding up steep grades. Torque is what makes the wheels on the bicycle go around. A great deal of research has been done to determine how to increase the torque applied by the rider to the rear wheel, while decreasing the torque required to make the wheels on the bicycle turn. The torque produced by the drive chain system is dependent upon the size of the chain ring being used, and the size of the rear sprocket being used. When the chain is on the smaller chain ring, the force applied through the chain is greater because the chain ring is closer to the axis of rotation and applies a larger force to equal the torque produced by the pedals.
Generally, efficiency is lost through the rotatory motion of the rider's foot movements as the foot presses upon the pedal and crank assembly at various stages of the rotary cycle. The maximum leverage—thus torque, is achieved by a foot when the pedal crank is at the forward horizontal position. Thus, in each rotary cycle there are two points in a full rotation of the crankshaft when the leverage imparted to the pedal crank is maximum. Conversely, in each rotary cycle there are two points when the leverage imparted to the pedal crank from the rider's foot is zero. These points of minimum leverage are developed when the pedal crank is at the vertical position. The momentum of the bicycle carries the pedal crank into the forward horizontal position where leverage can again be exerted.
There have been many attempts to improve the efficiency of a bicycle's operation. One specific focus has been to improve the torque generated by the rider's pedaling force in order to effectuate an increased speed, reduce the rider's fatigue, especially when the rider is traversing steep hills, and/or long rides when constant pedaling is required. It is well known that by increasing the length of the crank arms, i.e. the distance between the point of force application, i.e. the pedal, and the crank shaft, or bottom bracket, a greater force may be applied to the forward sprocket or chain ring. As a result, more torque can be applied to the rear wheel. However, because conventional bicycle drive chain system requires a rider's legs to move around in a complete revolution, the possible crank arm length is limited by the rider's anatomy and clearance with the ground. Using the conventional design, when the crank arm length is extended beyond a certain distance, it becomes uncomfortable or even impossible for the rider to make a complete turn of the crank arms while positioned on the bicycle. Further, at the extremes of aerodynamic positioning, when the crank arm rotates to the top of the pedal stroke, the hip of the rider is overly flexed. This places the rider's leg in a position where it is hard to apply force to the crank; as a result, producing power becomes more difficult. The longer the crank arm, the more difficult it becomes. So, in recent years, many riders have gravitated to shorter crank lengths, to reduce the amount of hip flexion as the crank passes over dead center vertical positions. Additionally, a longer crank arm can cause a pedal strike in tight corners. Further, many of the existing mechanisms for increasing energy into a drive chain system normally relate to the improvements and modifications of the cranks, forward sprocket, chain, and gears, etc., thus, have the disadvantage of not being easily adaptable to an ordinary bicycle and likewise not easily maintained by the rider.
In conventional systems, mechanical means of storing torque energy along the bicycle sprocket allows the rider to use this stored energy along the bicycle sprocket for the discussed applications. These conventional systems, however, require extensive modification to the bicycle. The present invention aims to improve the conventional systems by allocating the torque storing mechanism along the foot pedals. Thus, the present invention can be easily incorporated along the bicycle pedals with little to no altercations of the original bicycle sprocket assembly. Additionally, the present invention, when installed on each of the foot pedals, allows the rider to store and utilize additional torque energy and provides a more efficient means of storing torque energy than the conventional system.